On Thu, 3 Nov 2005, Martin J. Bligh wrote:> > But pages_min is based on the zone size, not the system size. And we> still cap it. Maybe that's just a mistake?

The per-zone watermarking is actually the "modern" and "working" approach.

We didn't always do it that way. I would not be at all surprised if the capping was from the global watermarking days.

Of course, I would _also_ not be at all surprised if it wasn't just out of habit. Most of the things where we try to scale things up by memory size, we cap for various reasons. Ie we tend to try to scale things like hash sizes for core data structures by memory size, but then we tend to cap them to "sane" versions.

So quite frankly, it's entirely possible that the capping is there not because it _ever_ was a good idea, but just because it's what we almost always do ;)